PURPOSE: To obtain a simple type terminal equipment which is suitable when communication is performed by commonly using one optical line whose length is unfixed, by constituting the equipment so that the talking device which depresses a call switch can become a master talking device and the other talking device can automatically become a slave talking device when it receives a burst digital signal.

CONSTITUTION: A transmission inputting circuit 1a is provided with plural input signal terminals and equipped with a sampling circuit, encoding circuit, etc., for converting analog signals into PCM signals. Similarly, a reception inputting circuit 1c is equipped with a circuit, etc., for demodulating the digital signals and separating them into analog signals and data. When a call switch CS is depressed, a master-slave state setting circuit 2 is set and its own talking device becomes a master and transmitting burst digital signals are outputted. A transmitting time setting circuit S9 is actuated when its own talking device becomes a slave and a control section 10 establishes whether its own talking device is the master device or slave device in accordance with control data extracted from a received digital signal processing circuit 8 and the output of the master-slave state setting circuit 2 and detects the timings of transmitting signals and receiving signals.